Light emitting device

Abstract

A light emitting device includes a package having a recess including an opening, a bottom surface, and an inner lateral surface extending from the bottom surface. A covering member covers at least one of the bottom surface or the inner lateral surface. A light emitting element is mounted on the bottom surface and has a light emitting surface. A sealing member is provided in the recess to cover the light emitting surface and has a light output surface having a concave shape. The sealing member includes a light-transmissive material containing a fluorescent material. A first film is provided on a part of the light output surface of the sealing member to reflect a part of the light emitted from the light emitting element, another part of the light emitted from the light emitting element being configured to pass through the first film.

What is claimed is: 
     
       1. A light emitting device comprising:
 a package having a recess comprising:
 an opening; 
 a bottom surface opposite to the opening in a height direction along a height of the light emitting device; and 
 an inner lateral surface extending from the bottom surface to the opening; 
 
 a covering member covering at least one of the bottom surface or the inner lateral surface; 
 a light emitting element mounted on the bottom surface of the recess, the light emitting element having a light emitting surface opposite to the bottom surface, a light being configured to be emitted from the light emitting surface; 
 a sealing member provided in the recess to cover the light emitting surface and having a light output surface via which the light is output from the sealing member, the light output surface being curved to have a concave shape, the sealing member comprising a light-transmissive material containing a fluorescent material to convert a wavelength of the light emitted from the light emitting element; and 
 a first film provided on a part of the light output surface of the sealing member to reflect a part of the light emitted from the light emitting element, another part of the light emitted from the light emitting element being configured to pass through the first film, 
 wherein the first film includes nano-particles having a size in a range of 1 nm to 100 nm, and 
 wherein a volume ratio of the nano-particles in the first film with respect to a total volume of the first film is 50% or greater. 
 
     
     
       2. The light emitting device according to  claim 1 ,
 wherein the covering member covers a first region of the bottom surface, and 
 wherein a second region of the bottom surface which is different from the first region is within the first film as viewed in the height direction. 
 
     
     
       3. The light emitting device according to  claim 1 ,
 wherein the covering member has a light-reflecting surface contacting the sealing member, inclined from the bottom surface at a predetermined angle. 
 
     
     
       4. The light emitting device according to  claim 3 ,
 wherein the predetermined angle of the light-reflecting surface is in a range of 1 degree to 70 degrees. 
 
     
     
       5. The light emitting device according to  claim 1 ,
 wherein the light output surface has an output surface outer peripheral edge and the first film has a film outer peripheral edge, and 
 wherein the film outer peripheral edge is apart from the output surface outer peripheral edge. 
 
     
     
       6. The light emitting device according to  claim 5 , wherein an entirety of the film outer peripheral edge is apart from the output surface outer peripheral edge. 
     
     
       7. The light emitting device according to  claim 1 , wherein the first film overlaps with the light emitting element in the height direction. 
     
     
       8. The light emitting device according to  claim 1 ,
 wherein the opening of the recess is defined by an upper edge of the package, and 
 wherein the upper edge and the first film are at least partially spaced apart from each other. 
 
     
     
       9. The light emitting device according to  claim 1 , wherein the first film has a first film lower surface opposing the light emitting surface, the first film lower surface having a first area that is equal to or larger than a second area of the light emitting surface and is also smaller than a third area of the sealing member upper surface as viewed in the height direction. 
     
     
       10. A light emitting device comprising:
 a light emitting element having a light emitting surface from which a light is emitted; 
 a sealing member provided on the light emitting surface of the light emitting element to cover the light emitting surface and having a light output surface via which the light is output from the sealing member, the sealing member comprising a light-transmissive material and a fluorescent material provided in the light-transmissive material to convert a wavelength of the light emitted from the light emitting element; 
 a package having a recess to house the light emitting element and the sealing member, the recess having a bottom surface on which the light emitting element is provided; 
 a covering member covering a covered region of the bottom surface of the recess to surround an exposed region of the bottom surface, the light emitting element being mounted on the exposed region so as to be separated from the covering member; and 
 a first film provided on a part of the light output surface of the sealing member to reflect a part of the light emitted from the light emitting element, another part of the light emitted from the light emitting element being configured to pass through the first film, and 
 wherein, as viewed in a height direction along a height of the light emitting device, the first film has a first area that overlaps with at least a portion of the exposed region, the first film being smaller than the light output surface of the sealing member, 
 wherein the first film includes nano-particles having a size in a range of 1 nm to 100 nm, and 
 wherein a volume ratio of the nano-particles in the first film with respect to a total volume of the first film is 50% or greater. 
 
     
     
       11. The light emitting device according to  claim 10 ,
 wherein the first film is located directly above the light emitting element in the height direction. 
 
     
     
       12. The light emitting device according to  claim 10 ,
 wherein the light output surface has an output surface outer peripheral edge and the first film has a film outer peripheral edge, and 
 wherein an entirety of the film outer peripheral edge is apart from the output surface outer peripheral edge. 
 
     
     
       13. The light emitting device according to  claim 10 ,
 wherein the nano-particles comprise titanium oxide. 
 
     
     
       14. The light emitting device according to  claim 10 ,
 wherein the first film has a thickness of 50 nm to 1 μm. 
 
     
     
       15. The light emitting device according to  claim 10 ,
 wherein the recess of the package has an inner lateral surface extending upward and outward from an outer peripheral edge of the bottom surface, and 
 wherein the covering member is integrally formed and is disposed so as to cover the covered region of the bottom surface and at least a portion of the inner lateral surface of the recess, the covering member having an upper surface provided between the bottom surface and inner lateral surface of the recess and curved in a concave shape. 
 
     
     
       16. The light emitting device according to  claim 10 ,
 wherein the covering member includes a resin member and a light-reflecting material provided in the resin member, and 
 wherein the light-reflecting material comprises at least one of an oxide of Ti, an oxide of Zr, an oxide of Nb, an oxide of Al, an oxide of Si, AN, MgF 2 , or BN. 
 
     
     
       17. The light emitting device according to  claim 10 ,
 wherein when viewed in the height direction, the first film has a film outer peripheral edge having a circular shape or an elliptic shape. 
 
     
     
       18. The light emitting device according to  claim 1 ,
 wherein the light emitting element has a peak emission wavelength of a light emitting element is in a range of 400 nm to 550 nm. 
 
     
     
       19. The light emitting device according to  claim 1 , further comprising a second film that surrounds the first film, at least a portion of the second film is disposed on an upper surface of the package. 
     
     
       20. The light emitting device according to  claim 1 ,
 wherein when viewed in the height direction, at least a portion of the first film overlaps with at least a portion of the covering member. 
 
     
     
       21. The light emitting device according to  claim 1 ,
 wherein at least a portion of the sealing member is exposed to an outside. 
 
     
     
       22. The light emitting device according to  claim 1 ,
 wherein an innermost edge of the covering member is a lowermost edge of the covering member in the height direction. 
 
     
     
       23. The light emitting device according to  claim 1 , further comprising an additional light emitting element mounted on the bottom surface of the recess,
 wherein the first film is disposed above both the light emitting element and the additional light emitting element in the height direction. 
 
     
     
       24. The light emitting device according to  claim 10 ,
 wherein the light emitting element has a peak emission wavelength of a light emitting element is in a range of 400 nm to 550 nm. 
 
     
     
       25. The light emitting device according to  claim 10 , further comprising a second film that surrounds the first film, at least a portion of the second film is disposed on an upper surface of the package. 
     
     
       26. The light emitting device according to  claim 10 ,
 wherein when viewed in the height direction, at least a portion of the first film overlaps with at least a portion of the covering member. 
 
     
     
       27. The light emitting device according to  claim 10 ,
 wherein at least a portion of the sealing member is exposed to an outside. 
 
     
     
       28. The light emitting device according to  claim 10 ,
 wherein an innermost edge of the covering member is a lowermost edge of the covering member in the height direction. 
 
     
     
       29. The light emitting device according to  claim 10 , further comprising an additional light emitting element mounted on the bottom surface of the recess,
 wherein the first film is disposed above both the light emitting element and the additional light emitting element in the height direction.